Surgeons have employed retractors formed by plates to retract tissue and provide access to a surgical site. These retractors are manually inserted by shifting aside the blood vessels, the nerves and the soft tissues by means of their end portions that are positioned adjacent to the spine. The retractors may be completed by pins which have ends inserted in the spine. The retractors can slide along these pins. Another technique teaches connecting the retractors about a frame so as to maintain them in the desired position and clear the operating area between the retractors.
Prior devices are not fully convenient to use in spinal surgery, in particular for positioning and maintaining retractors in a desired angular orientation relative to the operating space, in providing and maintaining an operating space in a posterior lateral approach, or for maintaining distraction of adjacent vertebrae. In addition, these prior systems are not fully compatible with spinal stabilization procedures both in the disc space and exteriorly of the disc space. Further, the design of such systems may require tissue retraction and exposure beyond that which may be desirable to minimize trauma to the patient as a result of the surgical procedure.
Thus, there is a need for systems for spinal surgery that facilitate distraction of adjacent vertebrae while maintaining tissue retraction and minimizing the invasiveness of the procedure.